In recent years, user terminals including a cellular transceiver and a wireless LAN transceiver (so-called dual terminals) have been becoming widespread. Wireless LAN access points managed by operators of cellular communication systems (hereinafter, simply referred to as “access points”) have also been increasing.
Therefore, the 3rd Generation Partnership Project (3GPP), a standardization project for cellular communication systems, plans to study technologies capable of strengthening cooperation between cellular communication systems and wireless LAN systems (see Non Patent Literature 1).
For example, a method of switching traffic to be transmitted and received between a user terminal and a cellular base station to a wireless LAN system (i.e. offloading) to distribute traffic load of the cellular base station to the wireless LAN system is conceivable.